[Pkg-mc-devel] Bug#556922: Console resize freezes mc causing system crash/hang

[Iustin Pop]

On Wed, Nov 18, 2009 at 11:54:31AM +0100, Benny Baumann wrote:
> Package: mc
> Version: 2:4.6.2~git20080311-4
> Severity: critical
> Justification: breaks the whole system
> 
> When running mc inside a screen session via SSH mc crashes as soon as you resize
> the window in which mc is displayed. When this error occures mc freezes and
> allocates memory in an endless loop in the background. Once system resources
> have been reached the entire system freezes. Sometimes (tested with a system
> with a Xen 3.2-1 hypervisor) this even might kernel-panic the hypervisor.
> 
> Steps to verify (the ones that worked for me):
> - Fire up a DomU with Xen (3.2-1)
> - Connect to that DomU by SSH
> - apt-get install screen mc
> - Fire up new screen session or take over an existing with screen -d -RR
> - In that screen session start mc
> - Resize the Window of the screen session
> - MC freezes (now wait a few seconds for MC to fill up the memory)
> --> The system completely hangs, probably with Kernel Panic
> 
> On the step where mc starts to hang have a view on top or htop regarding mc's
> memory usage which suddently increases rapidly. If you kill mc fast enough
> (before it reaches the maximum RAM available) no crash of the VM happens.

This doesn't happen anymore with the unstable version (2:4.7.0-pre1-3).
Could you try testing that and see if it indeed works for you (maybe by
building it for lenny?)

While this is indeed unpleasant, the fact that mc eats a lot of memory
should not kill the whole system, and is more likely a wrong system
configuration, I think.

regards,
iustin